Definition: You are given a question on high school microeconomics. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: You are told that the cross-price elasticity between goods X and Y is +2.0. This means that
(A)goods X and Y are normal goods. (B)goods X and Y are inferior goods. (C)goods X and Y are complementary goods. (D)goods X and Y are substitute goods.

D